1. Field of the Invention
Embodiments of the present invention generally relate to an encapsulated rotor for a permanent magnet submersible rotor.
2. Description of the Related Art
Electric submersible pumps (ESPs) are used to extract production fluid, such as crude oil and/or natural gas, from subterranean formations having insufficient pressure to naturally lift the production fluid to surface. ESPs are also used for water supply wells.
One major component of an ESP that has proved difficult to improve is the electric motor. Currently, electric motors used within ESPs are typically induction motors with elongated stator windings. These motors are extremely long, such as over 30 feet in length, and are not capable of having their speed controlled without the use of add-on expensive variable speed drives.
One possible replacement for the induction motor is the permanent magnet motor. Modern high performance magnet alloys are brittle materials, exhibiting relatively low strength and corrosion resistance. They are not capable of withstanding centrifugal stress induced by rotation.